A Low Cerebroplacental Ratio at 20-24 Weeks of Gestation Can Predict Reduced Fetal Size Later in Pregnancy or at Birth

Fetal Diagn Ther. 2018;44(2):112-123. doi: 10.1159/000479684. Epub 2017 Sep 20.

Abstract

Aim: To determine whether Doppler evaluation at 20-24 weeks of gestation can predict reduced fetal size later in pregnancy or at birth.

Methods: Fetal biometry and Doppler velocimetry were performed in 2,986 women with a singleton pregnancy at 20-24 weeks of gestation. Predictive performances of the umbilical artery pulsatility index (UA-PI) or the mean uterine artery pulsatility index (UtA-PI) >95th percentile, middle cerebral artery pulsatility index, or cerebroplacental ratio (CPR) <5th percentile for early small for gestational age (SGA; <34 weeks of gestation), late SGA (≥34 weeks of gestation), or SGA at birth (birthweight <10th percentile) were analyzed.

Results: The prevalence of early SGA, late SGA, and SGA at birth was 1.1, 9.6, and 14.7%, respectively. A CPR <5th percentile had a positive likelihood ratio (LR+) of 8.2 (95% confidence interval [CI] 5.7-12.0) for early SGA, a LR+ of 1.6 (95% CI 1.1-1.2) for late SGA, and a LR+ of 1.9 (95% CI 1.4-2.6) for SGA at birth. A UtA-PI >95th percentile was associated with late SGA and SGA at birth, while an UA-PI >95th percentile was associated with early SGA. Associations were higher in fetuses with an estimated fetal weight <10th percentile.

Conclusion: Fetal biometry and Doppler evaluation at 20-24 weeks of gestation can predict early and late SGA as well as SGA at birth.

Keywords: Adverse perinatal outcome; Birthweight; Doppler; Fetal growth restriction; Middle cerebral artery; Umbilical artery; Uterine arteries.

MeSH terms

  • Adult
  • Birth Weight / physiology*
  • Brain / diagnostic imaging*
  • Brain / growth & development
  • Cohort Studies
  • Female
  • Fetal Growth Retardation / diagnostic imaging*
  • Fetal Growth Retardation / epidemiology
  • Fetal Growth Retardation / physiopathology
  • Fetal Weight / physiology
  • Humans
  • Infant, Newborn
  • Infant, Small for Gestational Age / growth & development
  • Placenta / diagnostic imaging*
  • Placenta / physiology
  • Predictive Value of Tests
  • Pregnancy
  • Prenatal Care / methods
  • Ultrasonography, Prenatal / methods*
  • Young Adult